Case History: First Coiled-Tubing-Conveyed Live Well Intervention Run From a Semi-Submersible Platform in Brazil to Increase Perforation Length in a Deep Water Horizontal Wellbore

摘要

This paper will describe the first coiled-tubing-conveyedrnperforating (CTCP) jobs performed offshore in a horizontalrnwell in the Campos Basin, Rio de Janeiro, Brazil.rnThe operation was needed to obtain the objectives soughtrnafter for this well and also to provide a “learning curve” for arnmajor job that was to be run subsequent to this job using thernsame method. The second job was to be in a water depth ofrn968 ft., and more than 1,000 ft. of guns would be run. Bothrnjobs will be discussed in this paper along with the advantagesrngained on the second job from the first experience.rnThe first procedure required perforating of a 262-ft.rnInterval in a 92-degree horizontal well using 2 in., 6 SPF superrndeep penetration scalloped guns that would be coiled-tubingrndeployed through 3-? in. production tubing. The operationrnwas to be performed from a semi-submersible platform, andrnthe running and retrieving of the perforating guns would havernto be accomplished without killing the well so that damagingrncompletion fluids would not come into contact with thernreservoir. Requirements for the job were that a safe method bernused and that equipment and operational costs be kept atrnminimum so that a greater return on investment could bernrealized.rnOperational conditions included the following:rn1. Perforation was to be conducted with the well in anrnunderbalanced condition so that no formation damage wouldrnbe sustained.rn2. The operation had to be run from a semi-submersible 5rn3. That was set in a water depth of 430 ft. (2 nd job performedrnin a water depth of 968 ft.)rn4. The gun assembly would have to pass through a 2.81-in.rnMinimum ID.rnHe two jobs were completed under live well conditions,rnand both were successful. The estimated cost saving fromrnelimination of 3 days of rig time for the second job wasrnapproximately $360,000.rnEven more significant for this technology, there are norndocumented jobs in which this perforation length has beenrnattempted anywhere in the world from a semi-submersible orrnwhere the water-depth distance was used as a lubricator for thernguns.